• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.2
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• pp.120-129
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• 1995

A new nethod, namely multi-gain-levering, is proposed to improve FM response of the single frequency semiconductor lasers and applied to 1.55$\mu\textrm{m}$ InGaAsP/InP MGL(multi-gain-levered)-MQW-DFB-LD. This device consists of three sections with different bandgap energy and can be easily realized by selective MOVPE growth. Our analysis based on Green function showed that a flat, red-shifted, high FM efficiency of aove 15GHz/mA can be extected by novel gain-levering scheme.

• Proceedings of the Optical Society of Korea Conference
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• 1989.02a
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• pp.172-175
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• 1989

1.3${\mu}{\textrm}{m}$ surface-emitting GaInAsP/InP LED was fabricated by two-phase supercooling LPE technique. The lattice mismatch of the grown DH wafer was typically 0.03%. The processes involve SiO2 CVD, lithography, Zn diffusion, lift-off, lapping, annealing, and wire bonding. The fabricated LED shows the optical power of 600㎼ at 70mA driving current, differential resistance of 4$\Omega$, the f3dB of 35MHz, and the FWHM of 1040{{{{ ANGSTROM }}. The peak wavelength of the fabricated LED was at 1.29${\mu}{\textrm}{m}$(100mA).

• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.10
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• pp.33-40
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• 1993

A reflection type 16x8 S-SEED array from LP(Low Pressure)-MODVD-grown GaAs/AlGaAs extremely shallow quantum well(ESQW) structures, with 4% Al fraction, has been fabricated. Its intrinsic region consists of 50 pairs of alternating 100.angs. GaAs and 100.angs. $Al_{0.04}$Ga$_{0.96}$As layers. A multilayer reflector stack of $Al_{0.04}$/Ga$_{0.96}$ As(599$\AA$)/AlAs(723$\AA$) was incorporated for the reflection plane below the p-i-n structures. The device processing after the MOCVD growth includes the mesa etching, isolation etching, insulator deposition, p & n metallization, and AR(Anti-Reflection) coating. For switching characteristics of the S-SEED in the form of p-i-n ESQW diode, the maximum optical negative resistance was observed at 856nm. Reflectance measurements showed a change from 15.6% to 43.3% for +0.9V to -6V bias. The maximum contrast ration of the S-SEED array was 2.0 and all the 128 devices showed optical bistability with contrast ratios over 2.4 at 5V reverse bias.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.10
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• pp.6215-6222
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• 2014

This study examined the anti-cancer activity of gallic acid(GA) isolated from P. suffruticosa. was analyzed by ESI-MS, $^1H$-NMR, and $^{13}C$-NMR. The anti-cancer activity was evaluated by measuring the cancer size in CT-26 cancer-allograft mice treated with GA(100 mg/kg p.o) for 14 days. The change in body weight, acute toxicity, weight change of the liver and spleen and biomaker of the liver were evaluated in the mice after the GA treatment. As a result, the cancer size of the CT-26 cancer-allograft mice treated with GA decreased significantly compared to that of the cancer mice without significant changes in weight loss (p<0.05) and acute toxicity. The weight of the liver and spleen and ALT, AST and LPO levels increased by cancer were decreased significantly after the GA treatment, and the GSH levels decreased by cancer were increased significantly with the GA treatment (p<0.05). Therefore, GA could be an attractive lead for the development of anticancer agents.

• Nuclear Engineering and Technology
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• v.53 no.4
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• pp.1284-1288
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• 2021

In this work, we propose and design a GaN-based diode with a p-doped GaN (p-GaN) multi-well structure for high efficiency betavoltaic (BV) cells. The short-circuit current density (J_SC) and opencircuit voltage (V_OC) of the devices were investigated with variations of parameters such as the doping concentration, height, width of the p-GaN well region, well-to-well gap, and number of well regions. The J_SC of the device was significantly improved by a wider depletion area, which was obtained by applying the multi-well structure. The optimized device achieved a higher output power density by 8.6% than that of the conventional diode due to the enhancement of J_SC. The proposed device structure showed a high potential for a high efficiency BV cell candidate.

• ETRI Journal
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• v.30 no.3
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• pp.480-482
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• 2008

A novel InGaAsP/InP buried-ridge waveguide laser diode structure is proposed and demonstrated for use as a single-mode laser. The lateral mode of the proposed device can be controlled by adjusting the composition and thickness of the InGaAsP layer grown over the active region. Stable single-mode operation without kinks or beam-steering is achieved successfully with lateral and transverse in the junction plane even for the device with the ridge width of 9 ${\mu}m$ up to an injection current of 500 mA.

• Culinary science and hospitality research
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• v.17 no.3
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• pp.221-235
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• 2011

This study focuses on the qualitative characteristics of mackerel marinated with herb extracts. By differentiating the amounts of garlic, ginger and basil, the optimal amount of each ingredient to he added has been found. According to the result of the experiment, the highest level of preference has been shown for the combination of 3% of garlic, 3% of ginger and 2% of basil, generating the optimal amounts to be added. Since the pH change shown by the mackerel marinated by adding the optimal combination of 3% of garlic, 3% of ginger and 2% of basil is included in the range of pH 6.2-6.4, which is the initial point of decomposition for red-fleshed fish, it can be considered to be appropriate for the qualitative characteristics of the product. According to the differences test, GA3 bas shown the lowest level of strength, making it soft. Also, GA3 has shown the highest level of elasticity together with the characteristic of being moist. As a result, it can be said that garlic is better than ginger and basil. According to the preference test, GA3 has shown the highest level of preference in terms of appearance, flavor, texture, taste and overall preference. By considering the above results of the experiment, GA3 (3% of garlic) can be regarded as the optimal amount to be added.

• ETRI Journal
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• v.26 no.5
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• pp.475-480
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• 2004

Self-assembled InAs quantum dots (QDs) embedded in an InAlGaAs matrix were grown on an InP (001) using a solid-source molecular beam epitaxy and investigated using transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. TEM images indicated that the QD formation was strongly dependent on the growth behaviors of group III elements during the deposition of InAlGaAs barriers. We achieved a lasing operation of around 1.5 ${\mu}m$ at room temperature from uncoated QD lasers based on the InAlGaAs-InAlAs material system on the InP (001). The lasing wavelengths of the ridge-waveguide QD lasers were also dependent upon the cavity lengths due mainly to the gain required for the lasing operation.

• Proceedings of the Korean Vacuum Society Conference
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• 1995.02a
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• pp.39-40
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• 1995

• Proceedings of the Korean Vacuum Society Conference
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• 2008.02a
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• pp.117-117
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• 2008